Thirty-four black-footed ferrets were reintroduced to their natural habitat in Grasslands National Park in Saskatchewan in October. ((U.S. Fish and Wildlife Service))

A spring checkup on the fate of a group of black-footed ferrets, released to Saskatchewan's Grasslands National Park in the fall, shows that about one-third of the critters survived their first winter.

The park, in Saskatchewan's southwest, is one of several sites in North America chosen for the reintroduction of the species, whose numbers fell perilously close to extinction.

The last reliable Saskatchewan sighting of the animal was in 1937.

In October, 34 black-footed ferrets, raised at different zoos participating in an American-led recovery plan, were brought to Saskatchewan and released.

Parks Canada said Tuesday that a spring monitoring program determined 12 of the animals survived.